# Domain type: about

## Domain type and study type

The different domain types are associated with the different types of studies.

Each study type has its corresponding domain type. This information is summarized in the table below:

Study type | Domain type |
---|---|

2D plane study or 2D axisymmetric study |
2D domain |

3D study | 3D domain |

## 2D study type: plane or axisymmetric

The study domain of 2D domain type is used for the two types of 2D studies: 2D plane and 2D axisymmetric.

In both cases, the geometric description is carried out in the XY plane.

The study type is defined in the physics context at the moment of the definition of the application (choice of the model workspace):

- 2D plane : the geometry described is a plane cross-section of the device; the global results are computed for the chosen depth of the device.
- Axisymetric : the geometry described is a plane axial section of the device; the results correspond to the whole volume of the device.

## Length and angle units

Length and angle units are associated with the domain.

These units are used for the definition of entities attached to the domain: infinite box sizes, periodicity and/or symmetry planes position.